Concrete @ your Fingertips

Portland composite cements (CEM II cements) containing fly ash or limestone replacements are the most common form of bagged cement used for general purposes and can be purchased in 25 kg bags from local builders merchants. Some of these bags also contain an Air Entraining Agent and should not be used for rendering applications. Traditional OPC (CEM I Portland cement) is available often termed as High Strength.

Rapid hardening Portland cement (RHPC) is Portland cement that is modified (typically more finely ground) so that it hardens more rapidly at early ages after casting than Portland cement. It is rare this would be available in a bag but is distinguished as CEMI 52,5R

Sulfate resisting cement (SRC) is often used in buried concrete structures such as foundations in contact with aggressive grounds containing sulfate. In bags, SRC are now available as Portland fly-ash cement or Portland blastfurnace cement with a +SR designation or even as a CEMI+SR0 or CEMI+SR3.

Masonry cement is a blend of Portland cement and other constituents manufactured for the production of brick or blockwork mortars and renders. It should not be used for any other concrete application. This material is now of limited availability in bagged form.

Other cements, particularly very quick setting cements for repairs and minor works are readily available in a range of bag sizes.